Friction shock-absorbing mechanism



June 26, 1928. J. F. O'CONNOR FRICTION sHocK ABSORBING mmcmmsm Fined Afig. 19, 1925 2 Sheets-Sheet .1

' June 36, 1928.

J. F. o'coNNoR FRICTION SHOCK ABSORBING MECHANISM Fig Filed Aug. 19, 1925 2 Sheets-Sheet 2 Wa'tneaa fave/afar Jam fflfin wr i atented June 26, 1928.

entree stares FATENT QFFlCE.

JOHN F. OCONNOR, OF CHICAGO, ILLINOIS, ASSIGNOR TO W. H. MINER, LNG, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

,FRICTION SHOGK-ABSORBING MECHANISM.

Application filed August 19, 1925. Serial No. 51,105.

i This invention relates to improvements in friction shock absorbing mechanisms.

One object of the invention is to provide a friction shock absorbing mechanism, more particularly adapted for railway draft riggings, wherein is obtained high capacity due to large frictional areas together with differential wedge action during compression of the mechanism, and wherein is also obtained quick and certain release when the actuating force is reduced.

Another object of the invention is to provide a mechanism of the character indicated, including a plurality of plates, wherein the friction plates are so designed as to provide a certain amount of resiliency, which is effective during initial compression of the mechanism, thereby providing for prelimi-' nary light action.

Other objects and advantages of the invention will appear more clearly and fully from the description and claimshereinafter following.

In the drawings forming a part of this specification, Figure 1 is a longitudinal, hori- Zontal, sectional View of a portion of a railway draft rigging showing my improve ments in connection therewith. Figures 2 and 3 are transverse, vertical, sectional views corresponding respectively to the lines 22 and 33 of Figure 1.

In said drawings -10 indicate the usual channel shaped center or draft sills Crl of a railway car under-frame, to the inner sides of which are secured front stop lugs 11-11 and rear stop lugs 12- 12. The inner end portion of the draw bar is designated by 13, to which is operatively connected a hooded cast yoke 14 of well-known form. The shock absorbing mechanism proper is disposed within the yoke and the yoke and 7 parts therewithin are supported in operative position by a detachable saddle plate 1'. fixed to the draft sills. i v

The improved shock absorbing mechanism proper, as shown, comprises broadly, a pair of front'and rear follower casings A; two sets of U-shaped friction plates B-B; a

pair of tapered friction elements C-.-C; a

pair of U-shaped tapered friction members D-'-D;' a pair of friction shoes E-E; a pair of combined spring followers and wedge blocks F-I; tandem-arranged spring resistance element-s G-G; anda retainer bolt H.

outer end wall 18.

the adjacent arm 21. each element Chas a pair-of friction sur- The front and rear follower casings are of substantially identical design, each being in the form of a rectangular box-like casting having spaced horizontally disposed top and bottom'walls 16-16, spaced vertically disposed side walls 17-17, and a transverse The end wall 18 of each casing A co-operates with the corresponding stop lugs in the manner of the usuai follower. The side walls 17 of each casing have longitudinally disposed friction surfaces 1919 on the inner sides thereof.

The U-shaped friction plates BB are arranged in two sets at opposite ends of the mechanism, each set preferably comprising three members associated with the corresponding follower casing A. Each of the U-shapcd friction plates comprises a transverse section 20 and a pair of longitudinally extending spaced arms 2121, presenting plate-like friction members. The plate-like arms 21 of the rear set of U-shaped plates 13 are intercalated with the arms 21 of the front set. As shown in Figure 1, the inter calated' arms on each side of the mechanism are so arranged as to provide two roups of friction elements at opposite sides of the mechanism, the outermost arms 21 of the two groups being associated with the front set of U-shaped friction plates and cooperating with the friction shells and the innermost arms of said groups being associated with the rear set of U-shaped plates and co-operating with the tapered friction elements C. In this connection, it is pointed out that due to the U-shaped contour of the friction plates D,.a certain amount of resiliency is imparted to the same, thereby providing for preliminary action of the mechanism during a compression stroke.-

The tapered friction elements CC are arranged at opposite sides of the longitudinal axis of the mechanism and directly cooperate with the arms 21 at the correspond ing side of the gear. The elements C are of identical design, each being in the form of a relatively heavy plate-like member having a longitudinally disposed friction surface 22 on the outer sidethereof'co-operating with On the inner side,

faces 23 -23, each of the friction surfaces 23 being inclined slightly wlth reference to the longitudinal axis of the mechanism and converging outwardly with reference to the opiii) posed face 22 of the friction element. On the inner side, each friction element is also provided with a lateral enlargement 24 disposed centrally between the opposite ends thereof.

The pairs of U-shaped friction members D-D are of substantially identical construction. Each of the elements D comprises a transverse section 25 and apair of longitudinally disposed spaced arms 2626. Each of the arms 26 is provided with an outer friction surface 123 correspondingly inclined to and adapted to. co-operate with one of the friction surfaces 23 of the tapered faces 27 of the corresponding sections 26 of the front and rear U-shaped members D. On the inner side, each friction shoe has a pair of wedge faces 28 and 29, the wedge face 28 at one end of the shoe being'disposed at a relatively blunt angle with reference to the longitudinal axis of the mecha-' nism and the wedge face 29 at the opposite end of the shoe being disposed at a relatively keen wedge-acting angle with reference to the said axis. As clearly shown in Figure 1, the shoes E at the opposite sides of. the

mechanism are reversely arranged so that;

the blunt wedge face 28 of one of the shoes faces forwardly and the keen face thereof faces rearwardly, while the keen face of the other shoe faces forwardly and the blunt trace thereof faces rearwardly. Each of the shoes E is slotted vertically onthe outer side thereof, as indicated at 30, to receive the lug 2 1- of the corresponding tapered friction element Q. As shown in Figure 1, acertain amount of lateral play is. provided be tween. the lug and thebottom wall of the slot 80 of each co-operating shoe and tapered friction element C, while longitudinal relative movement of these parts is prevented thereby. .friction elements C are held in V ,tere d relation by the shoes E.

It will. thus be evident that the properly cen- The combined spring followers andwedge blocks F are two in number and cooperate respectively with the front and rear ends of the two friction shoes E. Each of the com 7 bi'ned spring followers and wedge blocks has a pair of inwardly converging wedge faces 128 and 12 9on the opposite sides thereof, the wedge face 128 being disposed at arelatively blunt angle to the ion gitudinal axis, while'the wedge face 129 is disposed at a relatively keen angle to said axis. As clearly shown in Figure 1, the

wedge faces 128 and 129 co-operate with the wedge faces 28 and 29 at the corresponding ends of the friction shoes E.

The spring resistance elements (ir -G are arranged in tandem, as most clearly shown in Figure 1, each unit comprising av rela tively heavy outer coil and a lighter inner coil, the outer coil of each unit having its opposite ends bearing respectively on the outer end of the corresponding spring follower F and the transverse section 25 of the corresponding U-shaped tapered friction member D. The inner coil of each unit has one end extending into a recess provided in the corresponding spring follower and the other end thereof bearing on the transverse section 25 of the corresponding member D. The springs of each unit are held in centered relation by an inwardly extending h ol low boss 31 on the wall 18 of the corresponding casing A. The transverse sections of the plates B and members D are suitably recessed, indicated at 32, to accommodate the corresponding boss 81. g

The mechanism is held in assembled relation and of uniform overall length by the retainer bolt H, which has its opposite ends anchored respectively to the bosses 31 of the front and rear follower casings The bolt H, in addition to holding the mechanism assembled, also-serves to maintain the parts under initial compression, 7 a I Compensation for wear of the various friction and wedge faces is had by the expansive action of the spring resistance eleinents G, which, as hereinbeforepointed out, are'preferably under initial compression.

The operation of my improved shock absorbing mechanism, assuming a compression stroke, is as follows: The front and rear follower casings will be moved relatively toward each other, carrying the correspond' ing sets of friction plates'B therewith and also compressing the front and rear units of the tande'merranged spring resistance elements G." Due to the pressure transmitted through the springs G, a wedging action will be set up between the combined spring followers and wedge blocks and the friction shoes,'sp,reading the shoes apart and placingthe friction elements under lateral pressure. During this action there will bea relatively high wedging action between the co-operating keen wedge faces of'the springfollowers and friction shoes, while there will be substantially no 'wedging aclot tion between. the co-operating blunt wedge facesthereof. During the compression of the mechanism a differential action will be had, due to the taper of the'friction ele-' m-ents C and the taper of the-friction membersD c0-0perating therewith, thereby effecting lateral approach toward the axis of.

the mechanism of the shoes E. The diiferi the front and rear sarin followers F the I rectly spring'follower oeing squeezed out from between the shoes. During the mitial comression of the mechanism-due to the resiliency ofthe U-shaped friction plates B, the plates will be flexed at the unsupported portions of the bends thereof until they fully bear on the end walls of the casings, providinga slight preliminary action before there is any relative movement of the arms of the friction plates'B on each other. The compression action of the mechanism will continue either until the actuating force is reduced or the inner ends of the casings A come into engagement, whereupon the actuating force will be transmitted dithrough the casingslA to the correstop lugs, thereby preventing the sponding being. subjected to excessive springs G from compression. IN hen the actuating-force is reduced, the parts will all be restored to normal position by the expansive action of the springs Gr. Itelease of the mechanism is greatly facilitated due to the blunt and keen angle arrangement of the co-acting wedge facesfof the spring followers and friction shoes, the included angle between the blunt and keen wedge faces of each set being such as to permit slippage on the same.

It will be evident to those skilled in the art that my invention is not limited to the blunt and keen angle arrangement of wedge faces, as it is within the scope of the invention to provide wedge faces which are all of the same angularity.

Although I have herein shown and described what I now consider the preferred manner of carrying out my invention, the same is merely illustrative and I contemplate all changes and modifications that come within the scope of the claims appended hereto.

I claim:

1. In a friction shock absorbing mechanism, the combination with relatively m0vable follower casings having interior friction surfaces; of a plurality of intercalated relatively movable friction elements, said intercalated elements being arranged iii-groups at opposite sides of the mechanism; means for placing said elements under lateral pressure, including wedge members interposed between said groups; a tapered friction ele ment cooperating with each group of intercalated elements; additional, separate tapered friction members interposed between the lateral pressure creating means and each first mentioned tapered friction element; and spring resistance means opposing relative movement of said intercalated friction elements and also opposing relative move ment of said follower casings.

2. In a friction shock absorbing mechathereby casings; 'a each group of elements, said member being" tapered at its opposite ends; a second friction member movablewlth each follower nism, the combination'with relatively movable follower casings having interior friction surfaces; of a plurality of intercalated relatively movable friction elements, said intercalated elements being arranged in groups at opposite sides of the mechanism and cooperating with the friction surfaces of the casings; atapered friction element cooperating with each group of elements; friction shoes; wedge means engaging said shoes; tapered friction members interposed between each-shoe and tapered friction element; and spring resistance means opposing relative movement of said intercalated elements and also opposing relative movement of said casings. i i v g 3. In a friction shock absorbing mechanism, the combination with relatively movable follower casings having interior friction surfaces; of a plurality of intercalated relatively movable" friction elements, said intercalated elements being arranged in groups at opposite sides of the mechanism and co operating withthe frictionsurfaces of the friction member cooperating with and having abut-ment means thereon, vsaid last named member having inclined friction surfaces cooperating with the friction surfaces at the corresponding ends of said tapered members; wedge friction shoes cooperating with said second named members; wedge blocks engaging said shoes; spring resistance means interposed between said wedge blocks and abutmentmeans of the corresponding friction members.

4. In a friction shock absorbing mechanism,.the combination with relatively movable follower casings having interior friction surfaces; of a plurality of intercalated friction elements, said elements being arranged in groups at opposite sides of the mechanism; of atapered friction element cooperating with each group of elements; front and rear friction members, each of said members being movable with one of said follower casings and each of said members having inclined friction surfaces on the opposite sidcs'thereof cooperating with the corresponding ends of said tapered elel'nents, said members having interior longitudinally disposed friction surfaces; a set of friction shoes, each shoe cooperating with the friction surfaces of said, front and rear mem bers; wedge blocks cooperating with said shoes; andspring resistance means interposed between said follower casings and wedge blocks.

5. In a friction shock absorbing mechanism, the combination with front and rear relatively movable follower casings, each having interior friction surfaces; of a plurality of fr1ct1on elements carried by each and follower casing, said elements each including a friction device movable with each follower casing, each of said devices including a pair of tapered plate-like sections disposed atopposite sides of the mechanism and cooperating with the corresponding ends of the tapered friction members; wedge spreading means cooperating with said tapered sections of said friction devices and sprlng resistance means opposing relative movement of said casing.

6."In a friction shock absorbing mechanism, the combination with front and rear follower casings having interior friction surfaces; 'U-shaped resilient friction ele ments carried by each casing, said friction elements on the front and rear casings having the arms thereof intercalated; a U- shaped friction member carried by each followercasing, each of said members having tapered arms; ,fr '1ct1on shoes cooperatingwith said'last named arins; wedge members engaging said shoes; a spring resistance interposed between each wedge member and the corresponding U-shaped friction member; and'a tapered friction element at each sideof the mechanism interposed between the intercalated arms. of the friction elements atone side of the mechanism and the corresponding tapered arms of the U-shaped members. H

7. In a friction shock absorbing mechanism, the combination with front and rear follower casings having interior longitudinally disposed friction surfaces;. a group of intercalated friction plates at each side of the mechanism;-a lateral pressure creating friction wedge: system, interposed between said groups of plates, said system including a'plurality of friction shoes; differential taperedfriction members interposed between said plates and shoes; spring resistance means'cooperating with said lateral pressure-creating system and follower casings; and inter-engaging means on said shoes and tapered members for maintaining thelatter in-centered position.

'In witness that I claim the foregoing I have hereunto subscribed my name this'15th day of-A'ugust; 1925.

1 JOHN F. OCONNOR 

